net/vmw_vsock/af_vsock.c

   1 /*
   2  * VMware vSockets Driver
   3  *
   4  * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation version 2 and no later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 /* Implementation notes:
  17  *
  18  * - There are two kinds of sockets: those created by user action (such as
  19  * calling socket(2)) and those created by incoming connection request packets.
  20  *
  21  * - There are two "global" tables, one for bound sockets (sockets that have
  22  * specified an address that they are responsible for) and one for connected
  23  * sockets (sockets that have established a connection with another socket).
  24  * These tables are "global" in that all sockets on the system are placed
  25  * within them. - Note, though, that the bound table contains an extra entry
  26  * for a list of unbound sockets and SOCK_DGRAM sockets will always remain in
  27  * that list. The bound table is used solely for lookup of sockets when packets
  28  * are received and that's not necessary for SOCK_DGRAM sockets since we create
  29  * a datagram handle for each and need not perform a lookup.  Keeping SOCK_DGRAM
  30  * sockets out of the bound hash buckets will reduce the chance of collisions
  31  * when looking for SOCK_STREAM sockets and prevents us from having to check the
  32  * socket type in the hash table lookups.
  33  *
  34  * - Sockets created by user action will either be "client" sockets that
  35  * initiate a connection or "server" sockets that listen for connections; we do
  36  * not support simultaneous connects (two "client" sockets connecting).
  37  *
  38  * - "Server" sockets are referred to as listener sockets throughout this
  39  * implementation because they are in the SS_LISTEN state.  When a connection
  40  * request is received (the second kind of socket mentioned above), we create a
  41  * new socket and refer to it as a pending socket.  These pending sockets are
  42  * placed on the pending connection list of the listener socket.  When future
  43  * packets are received for the address the listener socket is bound to, we
  44  * check if the source of the packet is from one that has an existing pending
  45  * connection.  If it does, we process the packet for the pending socket.  When
  46  * that socket reaches the connected state, it is removed from the listener
  47  * socket's pending list and enqueued in the listener socket's accept queue.
  48  * Callers of accept(2) will accept connected sockets from the listener socket's
  49  * accept queue.  If the socket cannot be accepted for some reason then it is
  50  * marked rejected.  Once the connection is accepted, it is owned by the user
  51  * process and the responsibility for cleanup falls with that user process.
  52  *
  53  * - It is possible that these pending sockets will never reach the connected
  54  * state; in fact, we may never receive another packet after the connection
  55  * request.  Because of this, we must schedule a cleanup function to run in the
  56  * future, after some amount of time passes where a connection should have been
  57  * established.  This function ensures that the socket is off all lists so it
  58  * cannot be retrieved, then drops all references to the socket so it is cleaned
  59  * up (sock_put() -> sk_free() -> our sk_destruct implementation).  Note this
  60  * function will also cleanup rejected sockets, those that reach the connected
  61  * state but leave it before they have been accepted.
  62  *
  63  * - Sockets created by user action will be cleaned up when the user process
  64  * calls close(2), causing our release implementation to be called. Our release
  65  * implementation will perform some cleanup then drop the last reference so our
  66  * sk_destruct implementation is invoked.  Our sk_destruct implementation will
  67  * perform additional cleanup that's common for both types of sockets.
  68  *
  69  * - A socket's reference count is what ensures that the structure won't be
  70  * freed.  Each entry in a list (such as the "global" bound and connected tables
  71  * and the listener socket's pending list and connected queue) ensures a
  72  * reference.  When we defer work until process context and pass a socket as our
  73  * argument, we must ensure the reference count is increased to ensure the
  74  * socket isn't freed before the function is run; the deferred function will
  75  * then drop the reference.
  76  */
  77
  78 #include <linux/types.h>
  79 #include <linux/bitops.h>
  80 #include <linux/cred.h>
  81 #include <linux/init.h>
  82 #include <linux/io.h>
  83 #include <linux/kernel.h>
  84 #include <linux/kmod.h>
  85 #include <linux/list.h>
  86 #include <linux/miscdevice.h>
  87 #include <linux/module.h>
  88 #include <linux/mutex.h>
  89 #include <linux/net.h>
  90 #include <linux/poll.h>
  91 #include <linux/skbuff.h>
  92 #include <linux/smp.h>
  93 #include <linux/socket.h>
  94 #include <linux/stddef.h>
  95 #include <linux/unistd.h>
  96 #include <linux/wait.h>
  97 #include <linux/workqueue.h>
  98 #include <net/sock.h>
  99
 100 #include "af_vsock.h"
 101
 102 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
 103 static void vsock_sk_destruct(struct sock *sk);
 104 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 105
 106 /* Protocol family. */
 107 static struct proto vsock_proto = {
 108         .name = "AF_VSOCK",
 109         .owner = THIS_MODULE,
 110         .obj_size = sizeof(struct vsock_sock),
 111 };
 112
 113 /* The default peer timeout indicates how long we will wait for a peer response
 114  * to a control message.
 115  */
 116 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
 117
 118 #define SS_LISTEN 255
 119
 120 static const struct vsock_transport *transport;
 121 static DEFINE_MUTEX(vsock_register_mutex);
 122
 123 /**** EXPORTS ****/
 124
 125 /* Get the ID of the local context.  This is transport dependent. */
 126
 127 int vm_sockets_get_local_cid(void)
 128 {
 129         return transport->get_local_cid();
 130 }
 131 EXPORT_SYMBOL_GPL(vm_sockets_get_local_cid);
 132
 133 /**** UTILS ****/
 134
 135 /* Each bound VSocket is stored in the bind hash table and each connected
 136  * VSocket is stored in the connected hash table.
 137  *
 138  * Unbound sockets are all put on the same list attached to the end of the hash
 139  * table (vsock_unbound_sockets).  Bound sockets are added to the hash table in
 140  * the bucket that their local address hashes to (vsock_bound_sockets(addr)
 141  * represents the list that addr hashes to).
 142  *
 143  * Specifically, we initialize the vsock_bind_table array to a size of
 144  * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through
 145  * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and
 146  * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets.  The hash function
 147  * mods with VSOCK_HASH_SIZE - 1 to ensure this.
 148  */
 149 #define VSOCK_HASH_SIZE         251
 150 #define MAX_PORT_RETRIES        24
 151
 152 #define VSOCK_HASH(addr)        ((addr)->svm_port % (VSOCK_HASH_SIZE - 1))
 153 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)])
 154 #define vsock_unbound_sockets     (&vsock_bind_table[VSOCK_HASH_SIZE])
 155
 156 /* XXX This can probably be implemented in a better way. */
 157 #define VSOCK_CONN_HASH(src, dst)                               \
 158         (((src)->svm_cid ^ (dst)->svm_port) % (VSOCK_HASH_SIZE - 1))
 159 #define vsock_connected_sockets(src, dst)               \
 160         (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)])
 161 #define vsock_connected_sockets_vsk(vsk)                                \
 162         vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr)
 163
 164 static struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
 165 static struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
 166 static DEFINE_SPINLOCK(vsock_table_lock);
 167
 168 static void vsock_init_tables(void)
 169 {
 170         int i;
 171
 172         for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++)
 173                 INIT_LIST_HEAD(&vsock_bind_table[i]);
 174
 175         for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++)
 176                 INIT_LIST_HEAD(&vsock_connected_table[i]);
 177 }
 178
 179 static void __vsock_insert_bound(struct list_head *list,
 180                                  struct vsock_sock *vsk)
 181 {
 182         sock_hold(&vsk->sk);
 183         list_add(&vsk->bound_table, list);
 184 }
 185
 186 static void __vsock_insert_connected(struct list_head *list,
 187                                      struct vsock_sock *vsk)
 188 {
 189         sock_hold(&vsk->sk);
 190         list_add(&vsk->connected_table, list);
 191 }
 192
 193 static void __vsock_remove_bound(struct vsock_sock *vsk)
 194 {
 195         list_del_init(&vsk->bound_table);
 196         sock_put(&vsk->sk);
 197 }
 198
 199 static void __vsock_remove_connected(struct vsock_sock *vsk)
 200 {
 201         list_del_init(&vsk->connected_table);
 202         sock_put(&vsk->sk);
 203 }
 204
 205 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
 206 {
 207         struct vsock_sock *vsk;
 208
 209         list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table)
 210                 if (addr->svm_port == vsk->local_addr.svm_port)
 211                         return sk_vsock(vsk);
 212
 213         return NULL;
 214 }
 215
 216 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
 217                                                   struct sockaddr_vm *dst)
 218 {
 219         struct vsock_sock *vsk;
 220
 221         list_for_each_entry(vsk, vsock_connected_sockets(src, dst),
 222                             connected_table) {
 223                 if (vsock_addr_equals_addr(src, &vsk->remote_addr) &&
 224                     dst->svm_port == vsk->local_addr.svm_port) {
 225                         return sk_vsock(vsk);
 226                 }
 227         }
 228
 229         return NULL;
 230 }
 231
 232 static bool __vsock_in_bound_table(struct vsock_sock *vsk)
 233 {
 234         return !list_empty(&vsk->bound_table);
 235 }
 236
 237 static bool __vsock_in_connected_table(struct vsock_sock *vsk)
 238 {
 239         return !list_empty(&vsk->connected_table);
 240 }
 241
 242 static void vsock_insert_unbound(struct vsock_sock *vsk)
 243 {
 244         spin_lock_bh(&vsock_table_lock);
 245         __vsock_insert_bound(vsock_unbound_sockets, vsk);
 246         spin_unlock_bh(&vsock_table_lock);
 247 }
 248
 249 void vsock_insert_connected(struct vsock_sock *vsk)
 250 {
 251         struct list_head *list = vsock_connected_sockets(
 252                 &vsk->remote_addr, &vsk->local_addr);
 253
 254         spin_lock_bh(&vsock_table_lock);
 255         __vsock_insert_connected(list, vsk);
 256         spin_unlock_bh(&vsock_table_lock);
 257 }
 258 EXPORT_SYMBOL_GPL(vsock_insert_connected);
 259
 260 void vsock_remove_bound(struct vsock_sock *vsk)
 261 {
 262         spin_lock_bh(&vsock_table_lock);
 263         __vsock_remove_bound(vsk);
 264         spin_unlock_bh(&vsock_table_lock);
 265 }
 266 EXPORT_SYMBOL_GPL(vsock_remove_bound);
 267
 268 void vsock_remove_connected(struct vsock_sock *vsk)
 269 {
 270         spin_lock_bh(&vsock_table_lock);
 271         __vsock_remove_connected(vsk);
 272         spin_unlock_bh(&vsock_table_lock);
 273 }
 274 EXPORT_SYMBOL_GPL(vsock_remove_connected);
 275
 276 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr)
 277 {
 278         struct sock *sk;
 279
 280         spin_lock_bh(&vsock_table_lock);
 281         sk = __vsock_find_bound_socket(addr);
 282         if (sk)
 283                 sock_hold(sk);
 284
 285         spin_unlock_bh(&vsock_table_lock);
 286
 287         return sk;
 288 }
 289 EXPORT_SYMBOL_GPL(vsock_find_bound_socket);
 290
 291 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
 292                                          struct sockaddr_vm *dst)
 293 {
 294         struct sock *sk;
 295
 296         spin_lock_bh(&vsock_table_lock);
 297         sk = __vsock_find_connected_socket(src, dst);
 298         if (sk)
 299                 sock_hold(sk);
 300
 301         spin_unlock_bh(&vsock_table_lock);
 302
 303         return sk;
 304 }
 305 EXPORT_SYMBOL_GPL(vsock_find_connected_socket);
 306
 307 static bool vsock_in_bound_table(struct vsock_sock *vsk)
 308 {
 309         bool ret;
 310
 311         spin_lock_bh(&vsock_table_lock);
 312         ret = __vsock_in_bound_table(vsk);
 313         spin_unlock_bh(&vsock_table_lock);
 314
 315         return ret;
 316 }
 317
 318 static bool vsock_in_connected_table(struct vsock_sock *vsk)
 319 {
 320         bool ret;
 321
 322         spin_lock_bh(&vsock_table_lock);
 323         ret = __vsock_in_connected_table(vsk);
 324         spin_unlock_bh(&vsock_table_lock);
 325
 326         return ret;
 327 }
 328
 329 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk))
 330 {
 331         int i;
 332
 333         spin_lock_bh(&vsock_table_lock);
 334
 335         for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) {
 336                 struct vsock_sock *vsk;
 337                 list_for_each_entry(vsk, &vsock_connected_table[i],
 338                                     connected_table);
 339                         fn(sk_vsock(vsk));
 340         }
 341
 342         spin_unlock_bh(&vsock_table_lock);
 343 }
 344 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket);
 345
 346 void vsock_add_pending(struct sock *listener, struct sock *pending)
 347 {
 348         struct vsock_sock *vlistener;
 349         struct vsock_sock *vpending;
 350
 351         vlistener = vsock_sk(listener);
 352         vpending = vsock_sk(pending);
 353
 354         sock_hold(pending);
 355         sock_hold(listener);
 356         list_add_tail(&vpending->pending_links, &vlistener->pending_links);
 357 }
 358 EXPORT_SYMBOL_GPL(vsock_add_pending);
 359
 360 void vsock_remove_pending(struct sock *listener, struct sock *pending)
 361 {
 362         struct vsock_sock *vpending = vsock_sk(pending);
 363
 364         list_del_init(&vpending->pending_links);
 365         sock_put(listener);
 366         sock_put(pending);
 367 }
 368 EXPORT_SYMBOL_GPL(vsock_remove_pending);
 369
 370 void vsock_enqueue_accept(struct sock *listener, struct sock *connected)
 371 {
 372         struct vsock_sock *vlistener;
 373         struct vsock_sock *vconnected;
 374
 375         vlistener = vsock_sk(listener);
 376         vconnected = vsock_sk(connected);
 377
 378         sock_hold(connected);
 379         sock_hold(listener);
 380         list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue);
 381 }
 382 EXPORT_SYMBOL_GPL(vsock_enqueue_accept);
 383
 384 static struct sock *vsock_dequeue_accept(struct sock *listener)
 385 {
 386         struct vsock_sock *vlistener;
 387         struct vsock_sock *vconnected;
 388
 389         vlistener = vsock_sk(listener);
 390
 391         if (list_empty(&vlistener->accept_queue))
 392                 return NULL;
 393
 394         vconnected = list_entry(vlistener->accept_queue.next,
 395                                 struct vsock_sock, accept_queue);
 396
 397         list_del_init(&vconnected->accept_queue);
 398         sock_put(listener);
 399         /* The caller will need a reference on the connected socket so we let
 400          * it call sock_put().
 401          */
 402
 403         return sk_vsock(vconnected);
 404 }
 405
 406 static bool vsock_is_accept_queue_empty(struct sock *sk)
 407 {
 408         struct vsock_sock *vsk = vsock_sk(sk);
 409         return list_empty(&vsk->accept_queue);
 410 }
 411
 412 static bool vsock_is_pending(struct sock *sk)
 413 {
 414         struct vsock_sock *vsk = vsock_sk(sk);
 415         return !list_empty(&vsk->pending_links);
 416 }
 417
 418 static int vsock_send_shutdown(struct sock *sk, int mode)
 419 {
 420         return transport->shutdown(vsock_sk(sk), mode);
 421 }
 422
 423 void vsock_pending_work(struct work_struct *work)
 424 {
 425         struct sock *sk;
 426         struct sock *listener;
 427         struct vsock_sock *vsk;
 428         bool cleanup;
 429
 430         vsk = container_of(work, struct vsock_sock, dwork.work);
 431         sk = sk_vsock(vsk);
 432         listener = vsk->listener;
 433         cleanup = true;
 434
 435         lock_sock(listener);
 436         lock_sock(sk);
 437
 438         if (vsock_is_pending(sk)) {
 439                 vsock_remove_pending(listener, sk);
 440         } else if (!vsk->rejected) {
 441                 /* We are not on the pending list and accept() did not reject
 442                  * us, so we must have been accepted by our user process.  We
 443                  * just need to drop our references to the sockets and be on
 444                  * our way.
 445                  */
 446                 cleanup = false;
 447                 goto out;
 448         }
 449
 450         listener->sk_ack_backlog--;
 451
 452         /* We need to remove ourself from the global connected sockets list so
 453          * incoming packets can't find this socket, and to reduce the reference
 454          * count.
 455          */
 456         if (vsock_in_connected_table(vsk))
 457                 vsock_remove_connected(vsk);
 458
 459         sk->sk_state = SS_FREE;
 460
 461 out:
 462         release_sock(sk);
 463         release_sock(listener);
 464         if (cleanup)
 465                 sock_put(sk);
 466
 467         sock_put(sk);
 468         sock_put(listener);
 469 }
 470 EXPORT_SYMBOL_GPL(vsock_pending_work);
 471
 472 /**** SOCKET OPERATIONS ****/
 473
 474 static int __vsock_bind_stream(struct vsock_sock *vsk,
 475                                struct sockaddr_vm *addr)
 476 {
 477         static u32 port = LAST_RESERVED_PORT + 1;
 478         struct sockaddr_vm new_addr;
 479
 480         vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
 481
 482         if (addr->svm_port == VMADDR_PORT_ANY) {
 483                 bool found = false;
 484                 unsigned int i;
 485
 486                 for (i = 0; i < MAX_PORT_RETRIES; i++) {
 487                         if (port <= LAST_RESERVED_PORT)
 488                                 port = LAST_RESERVED_PORT + 1;
 489
 490                         new_addr.svm_port = port++;
 491
 492                         if (!__vsock_find_bound_socket(&new_addr)) {
 493                                 found = true;
 494                                 break;
 495                         }
 496                 }
 497
 498                 if (!found)
 499                         return -EADDRNOTAVAIL;
 500         } else {
 501                 /* If port is in reserved range, ensure caller
 502                  * has necessary privileges.
 503                  */
 504                 if (addr->svm_port <= LAST_RESERVED_PORT &&
 505                     !capable(CAP_NET_BIND_SERVICE)) {
 506                         return -EACCES;
 507                 }
 508
 509                 if (__vsock_find_bound_socket(&new_addr))
 510                         return -EADDRINUSE;
 511         }
 512
 513         vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
 514
 515         /* Remove stream sockets from the unbound list and add them to the hash
 516          * table for easy lookup by its address.  The unbound list is simply an
 517          * extra entry at the end of the hash table, a trick used by AF_UNIX.
 518          */
 519         __vsock_remove_bound(vsk);
 520         __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
 521
 522         return 0;
 523 }
 524
 525 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 526                               struct sockaddr_vm *addr)
 527 {
 528         return transport->dgram_bind(vsk, addr);
 529 }
 530
 531 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 532 {
 533         struct vsock_sock *vsk = vsock_sk(sk);
 534         u32 cid;
 535         int retval;
 536
 537         /* First ensure this socket isn't already bound. */
 538         if (vsock_addr_bound(&vsk->local_addr))
 539                 return -EINVAL;
 540
 541         /* Now bind to the provided address or select appropriate values if
 542          * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY).  Note that
 543          * like AF_INET prevents binding to a non-local IP address (in most
 544          * cases), we only allow binding to the local CID.
 545          */
 546         cid = transport->get_local_cid();
 547         if (addr->svm_cid != cid && addr->svm_cid != VMADDR_CID_ANY)
 548                 return -EADDRNOTAVAIL;
 549
 550         switch (sk->sk_socket->type) {
 551         case SOCK_STREAM:
 552                 spin_lock_bh(&vsock_table_lock);
 553                 retval = __vsock_bind_stream(vsk, addr);
 554                 spin_unlock_bh(&vsock_table_lock);
 555                 break;
 556
 557         case SOCK_DGRAM:
 558                 retval = __vsock_bind_dgram(vsk, addr);
 559                 break;
 560
 561         default:
 562                 retval = -EINVAL;
 563                 break;
 564         }
 565
 566         return retval;
 567 }
 568
 569 struct sock *__vsock_create(struct net *net,
 570                             struct socket *sock,
 571                             struct sock *parent,
 572                             gfp_t priority,
 573                             unsigned short type)
 574 {
 575         struct sock *sk;
 576         struct vsock_sock *psk;
 577         struct vsock_sock *vsk;
 578
 579         sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto);
 580         if (!sk)
 581                 return NULL;
 582
 583         sock_init_data(sock, sk);
 584
 585         /* sk->sk_type is normally set in sock_init_data, but only if sock is
 586          * non-NULL. We make sure that our sockets always have a type by
 587          * setting it here if needed.
 588          */
 589         if (!sock)
 590                 sk->sk_type = type;
 591
 592         vsk = vsock_sk(sk);
 593         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 594         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 595
 596         sk->sk_destruct = vsock_sk_destruct;
 597         sk->sk_backlog_rcv = vsock_queue_rcv_skb;
 598         sk->sk_state = 0;
 599         sock_reset_flag(sk, SOCK_DONE);
 600
 601         INIT_LIST_HEAD(&vsk->bound_table);
 602         INIT_LIST_HEAD(&vsk->connected_table);
 603         vsk->listener = NULL;
 604         INIT_LIST_HEAD(&vsk->pending_links);
 605         INIT_LIST_HEAD(&vsk->accept_queue);
 606         vsk->rejected = false;
 607         vsk->sent_request = false;
 608         vsk->ignore_connecting_rst = false;
 609         vsk->peer_shutdown = 0;
 610
 611         psk = parent ? vsock_sk(parent) : NULL;
 612         if (parent) {
 613                 vsk->trusted = psk->trusted;
 614                 vsk->owner = get_cred(psk->owner);
 615                 vsk->connect_timeout = psk->connect_timeout;
 616         } else {
 617                 vsk->trusted = capable(CAP_NET_ADMIN);
 618                 vsk->owner = get_current_cred();
 619                 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
 620         }
 621
 622         if (transport->init(vsk, psk) < 0) {
 623                 sk_free(sk);
 624                 return NULL;
 625         }
 626
 627         if (sock)
 628                 vsock_insert_unbound(vsk);
 629
 630         return sk;
 631 }
 632 EXPORT_SYMBOL_GPL(__vsock_create);
 633
 634 static void __vsock_release(struct sock *sk)
 635 {
 636         if (sk) {
 637                 struct sk_buff *skb;
 638                 struct sock *pending;
 639                 struct vsock_sock *vsk;
 640
 641                 vsk = vsock_sk(sk);
 642                 pending = NULL; /* Compiler warning. */
 643
 644                 if (vsock_in_bound_table(vsk))
 645                         vsock_remove_bound(vsk);
 646
 647                 if (vsock_in_connected_table(vsk))
 648                         vsock_remove_connected(vsk);
 649
 650                 transport->release(vsk);
 651
 652                 lock_sock(sk);
 653                 sock_orphan(sk);
 654                 sk->sk_shutdown = SHUTDOWN_MASK;
 655
 656                 while ((skb = skb_dequeue(&sk->sk_receive_queue)))
 657                         kfree_skb(skb);
 658
 659                 /* Clean up any sockets that never were accepted. */
 660                 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
 661                         __vsock_release(pending);
 662                         sock_put(pending);
 663                 }
 664
 665                 release_sock(sk);
 666                 sock_put(sk);
 667         }
 668 }
 669
 670 static void vsock_sk_destruct(struct sock *sk)
 671 {
 672         struct vsock_sock *vsk = vsock_sk(sk);
 673
 674         transport->destruct(vsk);
 675
 676         /* When clearing these addresses, there's no need to set the family and
 677          * possibly register the address family with the kernel.
 678          */
 679         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 680         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 681
 682         put_cred(vsk->owner);
 683 }
 684
 685 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 686 {
 687         int err;
 688
 689         err = sock_queue_rcv_skb(sk, skb);
 690         if (err)
 691                 kfree_skb(skb);
 692
 693         return err;
 694 }
 695
 696 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 697 {
 698         return transport->stream_has_data(vsk);
 699 }
 700 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
 701
 702 s64 vsock_stream_has_space(struct vsock_sock *vsk)
 703 {
 704         return transport->stream_has_space(vsk);
 705 }
 706 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
 707
 708 static int vsock_release(struct socket *sock)
 709 {
 710         __vsock_release(sock->sk);
 711         sock->sk = NULL;
 712         sock->state = SS_FREE;
 713
 714         return 0;
 715 }
 716
 717 static int
 718 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 719 {
 720         int err;
 721         struct sock *sk;
 722         struct sockaddr_vm *vm_addr;
 723
 724         sk = sock->sk;
 725
 726         if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
 727                 return -EINVAL;
 728
 729         lock_sock(sk);
 730         err = __vsock_bind(sk, vm_addr);
 731         release_sock(sk);
 732
 733         return err;
 734 }
 735
 736 static int vsock_getname(struct socket *sock,
 737                          struct sockaddr *addr, int *addr_len, int peer)
 738 {
 739         int err;
 740         struct sock *sk;
 741         struct vsock_sock *vsk;
 742         struct sockaddr_vm *vm_addr;
 743
 744         sk = sock->sk;
 745         vsk = vsock_sk(sk);
 746         err = 0;
 747
 748         lock_sock(sk);
 749
 750         if (peer) {
 751                 if (sock->state != SS_CONNECTED) {
 752                         err = -ENOTCONN;
 753                         goto out;
 754                 }
 755                 vm_addr = &vsk->remote_addr;
 756         } else {
 757                 vm_addr = &vsk->local_addr;
 758         }
 759
 760         if (!vm_addr) {
 761                 err = -EINVAL;
 762                 goto out;
 763         }
 764
 765         /* sys_getsockname() and sys_getpeername() pass us a
 766          * MAX_SOCK_ADDR-sized buffer and don't set addr_len.  Unfortunately
 767          * that macro is defined in socket.c instead of .h, so we hardcode its
 768          * value here.
 769          */
 770         BUILD_BUG_ON(sizeof(*vm_addr) > 128);
 771         memcpy(addr, vm_addr, sizeof(*vm_addr));
 772         *addr_len = sizeof(*vm_addr);
 773
 774 out:
 775         release_sock(sk);
 776         return err;
 777 }
 778
 779 static int vsock_shutdown(struct socket *sock, int mode)
 780 {
 781         int err;
 782         struct sock *sk;
 783
 784         /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
 785          * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
 786          * here like the other address families do.  Note also that the
 787          * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
 788          * which is what we want.
 789          */
 790         mode++;
 791
 792         if ((mode & ~SHUTDOWN_MASK) || !mode)
 793                 return -EINVAL;
 794
 795         /* If this is a STREAM socket and it is not connected then bail out
 796          * immediately.  If it is a DGRAM socket then we must first kick the
 797          * socket so that it wakes up from any sleeping calls, for example
 798          * recv(), and then afterwards return the error.
 799          */
 800
 801         sk = sock->sk;
 802         if (sock->state == SS_UNCONNECTED) {
 803                 err = -ENOTCONN;
 804                 if (sk->sk_type == SOCK_STREAM)
 805                         return err;
 806         } else {
 807                 sock->state = SS_DISCONNECTING;
 808                 err = 0;
 809         }
 810
 811         /* Receive and send shutdowns are treated alike. */
 812         mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
 813         if (mode) {
 814                 lock_sock(sk);
 815                 sk->sk_shutdown |= mode;
 816                 sk->sk_state_change(sk);
 817                 release_sock(sk);
 818
 819                 if (sk->sk_type == SOCK_STREAM) {
 820                         sock_reset_flag(sk, SOCK_DONE);
 821                         vsock_send_shutdown(sk, mode);
 822                 }
 823         }
 824
 825         return err;
 826 }
 827
 828 static unsigned int vsock_poll(struct file *file, struct socket *sock,
 829                                poll_table *wait)
 830 {
 831         struct sock *sk;
 832         unsigned int mask;
 833         struct vsock_sock *vsk;
 834
 835         sk = sock->sk;
 836         vsk = vsock_sk(sk);
 837
 838         poll_wait(file, sk_sleep(sk), wait);
 839         mask = 0;
 840
 841         if (sk->sk_err)
 842                 /* Signify that there has been an error on this socket. */
 843                 mask |= POLLERR;
 844
 845         /* INET sockets treat local write shutdown and peer write shutdown as a
 846          * case of POLLHUP set.
 847          */
 848         if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
 849             ((sk->sk_shutdown & SEND_SHUTDOWN) &&
 850              (vsk->peer_shutdown & SEND_SHUTDOWN))) {
 851                 mask |= POLLHUP;
 852         }
 853
 854         if (sk->sk_shutdown & RCV_SHUTDOWN ||
 855             vsk->peer_shutdown & SEND_SHUTDOWN) {
 856                 mask |= POLLRDHUP;
 857         }
 858
 859         if (sock->type == SOCK_DGRAM) {
 860                 /* For datagram sockets we can read if there is something in
 861                  * the queue and write as long as the socket isn't shutdown for
 862                  * sending.
 863                  */
 864                 if (!skb_queue_empty(&sk->sk_receive_queue) ||
 865                     (sk->sk_shutdown & RCV_SHUTDOWN)) {
 866                         mask |= POLLIN | POLLRDNORM;
 867                 }
 868
 869                 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 870                         mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 871
 872         } else if (sock->type == SOCK_STREAM) {
 873                 lock_sock(sk);
 874
 875                 /* Listening sockets that have connections in their accept
 876                  * queue can be read.
 877                  */
 878                 if (sk->sk_state == SS_LISTEN
 879                     && !vsock_is_accept_queue_empty(sk))
 880                         mask |= POLLIN | POLLRDNORM;
 881
 882                 /* If there is something in the queue then we can read. */
 883                 if (transport->stream_is_active(vsk) &&
 884                     !(sk->sk_shutdown & RCV_SHUTDOWN)) {
 885                         bool data_ready_now = false;
 886                         int ret = transport->notify_poll_in(
 887                                         vsk, 1, &data_ready_now);
 888                         if (ret < 0) {
 889                                 mask |= POLLERR;
 890                         } else {
 891                                 if (data_ready_now)
 892                                         mask |= POLLIN | POLLRDNORM;
 893
 894                         }
 895                 }
 896
 897                 /* Sockets whose connections have been closed, reset, or
 898                  * terminated should also be considered read, and we check the
 899                  * shutdown flag for that.
 900                  */
 901                 if (sk->sk_shutdown & RCV_SHUTDOWN ||
 902                     vsk->peer_shutdown & SEND_SHUTDOWN) {
 903                         mask |= POLLIN | POLLRDNORM;
 904                 }
 905
 906                 /* Connected sockets that can produce data can be written. */
 907                 if (sk->sk_state == SS_CONNECTED) {
 908                         if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
 909                                 bool space_avail_now = false;
 910                                 int ret = transport->notify_poll_out(
 911                                                 vsk, 1, &space_avail_now);
 912                                 if (ret < 0) {
 913                                         mask |= POLLERR;
 914                                 } else {
 915                                         if (space_avail_now)
 916                                                 /* Remove POLLWRBAND since INET
 917                                                  * sockets are not setting it.
 918                                                  */
 919                                                 mask |= POLLOUT | POLLWRNORM;
 920
 921                                 }
 922                         }
 923                 }
 924
 925                 /* Simulate INET socket poll behaviors, which sets
 926                  * POLLOUT|POLLWRNORM when peer is closed and nothing to read,
 927                  * but local send is not shutdown.
 928                  */
 929                 if (sk->sk_state == SS_UNCONNECTED) {
 930                         if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 931                                 mask |= POLLOUT | POLLWRNORM;
 932
 933                 }
 934
 935                 release_sock(sk);
 936         }
 937
 938         return mask;
 939 }
 940
 941 static int vsock_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock,
 942                                struct msghdr *msg, size_t len)
 943 {
 944         int err;
 945         struct sock *sk;
 946         struct vsock_sock *vsk;
 947         struct sockaddr_vm *remote_addr;
 948
 949         if (msg->msg_flags & MSG_OOB)
 950                 return -EOPNOTSUPP;
 951
 952         /* For now, MSG_DONTWAIT is always assumed... */
 953         err = 0;
 954         sk = sock->sk;
 955         vsk = vsock_sk(sk);
 956
 957         lock_sock(sk);
 958
 959         if (!vsock_addr_bound(&vsk->local_addr)) {
 960                 struct sockaddr_vm local_addr;
 961
 962                 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 963                 err = __vsock_bind(sk, &local_addr);
 964                 if (err != 0)
 965                         goto out;
 966
 967         }
 968
 969         /* If the provided message contains an address, use that.  Otherwise
 970          * fall back on the socket's remote handle (if it has been connected).
 971          */
 972         if (msg->msg_name &&
 973             vsock_addr_cast(msg->msg_name, msg->msg_namelen,
 974                             &remote_addr) == 0) {
 975                 /* Ensure this address is of the right type and is a valid
 976                  * destination.
 977                  */
 978
 979                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
 980                         remote_addr->svm_cid = transport->get_local_cid();
 981
 982                 if (!vsock_addr_bound(remote_addr)) {
 983                         err = -EINVAL;
 984                         goto out;
 985                 }
 986         } else if (sock->state == SS_CONNECTED) {
 987                 remote_addr = &vsk->remote_addr;
 988
 989                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
 990                         remote_addr->svm_cid = transport->get_local_cid();
 991
 992                 /* XXX Should connect() or this function ensure remote_addr is
 993                  * bound?
 994                  */
 995                 if (!vsock_addr_bound(&vsk->remote_addr)) {
 996                         err = -EINVAL;
 997                         goto out;
 998                 }
 999         } else {
1000                 err = -EINVAL;
1001                 goto out;
1002         }
1003
1004         if (!transport->dgram_allow(remote_addr->svm_cid,
1005                                     remote_addr->svm_port)) {
1006                 err = -EINVAL;
1007                 goto out;
1008         }
1009
1010         err = transport->dgram_enqueue(vsk, remote_addr, msg->msg_iov, len);
1011
1012 out:
1013         release_sock(sk);
1014         return err;
1015 }
1016
1017 static int vsock_dgram_connect(struct socket *sock,
1018                                struct sockaddr *addr, int addr_len, int flags)
1019 {
1020         int err;
1021         struct sock *sk;
1022         struct vsock_sock *vsk;
1023         struct sockaddr_vm *remote_addr;
1024
1025         sk = sock->sk;
1026         vsk = vsock_sk(sk);
1027
1028         err = vsock_addr_cast(addr, addr_len, &remote_addr);
1029         if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1030                 lock_sock(sk);
1031                 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1032                                 VMADDR_PORT_ANY);
1033                 sock->state = SS_UNCONNECTED;
1034                 release_sock(sk);
1035                 return 0;
1036         } else if (err != 0)
1037                 return -EINVAL;
1038
1039         lock_sock(sk);
1040
1041         if (!vsock_addr_bound(&vsk->local_addr)) {
1042                 struct sockaddr_vm local_addr;
1043
1044                 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
1045                 err = __vsock_bind(sk, &local_addr);
1046                 if (err != 0)
1047                         goto out;
1048
1049         }
1050
1051         if (!transport->dgram_allow(remote_addr->svm_cid,
1052                                     remote_addr->svm_port)) {
1053                 err = -EINVAL;
1054                 goto out;
1055         }
1056
1057         memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1058         sock->state = SS_CONNECTED;
1059
1060 out:
1061         release_sock(sk);
1062         return err;
1063 }
1064
1065 static int vsock_dgram_recvmsg(struct kiocb *kiocb, struct socket *sock,
1066                                struct msghdr *msg, size_t len, int flags)
1067 {
1068         return transport->dgram_dequeue(kiocb, vsock_sk(sock->sk), msg, len,
1069                                         flags);
1070 }
1071
1072 static const struct proto_ops vsock_dgram_ops = {
1073         .family = PF_VSOCK,
1074         .owner = THIS_MODULE,
1075         .release = vsock_release,
1076         .bind = vsock_bind,
1077         .connect = vsock_dgram_connect,
1078         .socketpair = sock_no_socketpair,
1079         .accept = sock_no_accept,
1080         .getname = vsock_getname,
1081         .poll = vsock_poll,
1082         .ioctl = sock_no_ioctl,
1083         .listen = sock_no_listen,
1084         .shutdown = vsock_shutdown,
1085         .setsockopt = sock_no_setsockopt,
1086         .getsockopt = sock_no_getsockopt,
1087         .sendmsg = vsock_dgram_sendmsg,
1088         .recvmsg = vsock_dgram_recvmsg,
1089         .mmap = sock_no_mmap,
1090         .sendpage = sock_no_sendpage,
1091 };
1092
1093 static void vsock_connect_timeout(struct work_struct *work)
1094 {
1095         struct sock *sk;
1096         struct vsock_sock *vsk;
1097
1098         vsk = container_of(work, struct vsock_sock, dwork.work);
1099         sk = sk_vsock(vsk);
1100
1101         lock_sock(sk);
1102         if (sk->sk_state == SS_CONNECTING &&
1103             (sk->sk_shutdown != SHUTDOWN_MASK)) {
1104                 sk->sk_state = SS_UNCONNECTED;
1105                 sk->sk_err = ETIMEDOUT;
1106                 sk->sk_error_report(sk);
1107         }
1108         release_sock(sk);
1109
1110         sock_put(sk);
1111 }
1112
1113 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1114                                 int addr_len, int flags)
1115 {
1116         int err;
1117         struct sock *sk;
1118         struct vsock_sock *vsk;
1119         struct sockaddr_vm *remote_addr;
1120         long timeout;
1121         DEFINE_WAIT(wait);
1122
1123         err = 0;
1124         sk = sock->sk;
1125         vsk = vsock_sk(sk);
1126
1127         lock_sock(sk);
1128
1129         /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1130         switch (sock->state) {
1131         case SS_CONNECTED:
1132                 err = -EISCONN;
1133                 goto out;
1134         case SS_DISCONNECTING:
1135                 err = -EINVAL;
1136                 goto out;
1137         case SS_CONNECTING:
1138                 /* This continues on so we can move sock into the SS_CONNECTED
1139                  * state once the connection has completed (at which point err
1140                  * will be set to zero also).  Otherwise, we will either wait
1141                  * for the connection or return -EALREADY should this be a
1142                  * non-blocking call.
1143                  */
1144                 err = -EALREADY;
1145                 break;
1146         default:
1147                 if ((sk->sk_state == SS_LISTEN) ||
1148                     vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1149                         err = -EINVAL;
1150                         goto out;
1151                 }
1152
1153                 /* The hypervisor and well-known contexts do not have socket
1154                  * endpoints.
1155                  */
1156                 if (!transport->stream_allow(remote_addr->svm_cid,
1157                                              remote_addr->svm_port)) {
1158                         err = -ENETUNREACH;
1159                         goto out;
1160                 }
1161
1162                 /* Set the remote address that we are connecting to. */
1163                 memcpy(&vsk->remote_addr, remote_addr,
1164                        sizeof(vsk->remote_addr));
1165
1166                 /* Autobind this socket to the local address if necessary. */
1167                 if (!vsock_addr_bound(&vsk->local_addr)) {
1168                         struct sockaddr_vm local_addr;
1169
1170                         vsock_addr_init(&local_addr, VMADDR_CID_ANY,
1171                                         VMADDR_PORT_ANY);
1172                         err = __vsock_bind(sk, &local_addr);
1173                         if (err != 0)
1174                                 goto out;
1175
1176                 }
1177
1178                 sk->sk_state = SS_CONNECTING;
1179
1180                 err = transport->connect(vsk);
1181                 if (err < 0)
1182                         goto out;
1183
1184                 /* Mark sock as connecting and set the error code to in
1185                  * progress in case this is a non-blocking connect.
1186                  */
1187                 sock->state = SS_CONNECTING;
1188                 err = -EINPROGRESS;
1189         }
1190
1191         /* The receive path will handle all communication until we are able to
1192          * enter the connected state.  Here we wait for the connection to be
1193          * completed or a notification of an error.
1194          */
1195         timeout = vsk->connect_timeout;
1196         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1197
1198         while (sk->sk_state != SS_CONNECTED && sk->sk_err == 0) {
1199                 if (flags & O_NONBLOCK) {
1200                         /* If we're not going to block, we schedule a timeout
1201                          * function to generate a timeout on the connection
1202                          * attempt, in case the peer doesn't respond in a
1203                          * timely manner. We hold on to the socket until the
1204                          * timeout fires.
1205                          */
1206                         sock_hold(sk);
1207                         INIT_DELAYED_WORK(&vsk->dwork,
1208                                           vsock_connect_timeout);
1209                         schedule_delayed_work(&vsk->dwork, timeout);
1210
1211                         /* Skip ahead to preserve error code set above. */
1212                         goto out_wait;
1213                 }
1214
1215                 release_sock(sk);
1216                 timeout = schedule_timeout(timeout);
1217                 lock_sock(sk);
1218
1219                 if (signal_pending(current)) {
1220                         err = sock_intr_errno(timeout);
1221                         goto out_wait_error;
1222                 } else if (timeout == 0) {
1223                         err = -ETIMEDOUT;
1224                         goto out_wait_error;
1225                 }
1226
1227                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1228         }
1229
1230         if (sk->sk_err) {
1231                 err = -sk->sk_err;
1232                 goto out_wait_error;
1233         } else
1234                 err = 0;
1235
1236 out_wait:
1237         finish_wait(sk_sleep(sk), &wait);
1238 out:
1239         release_sock(sk);
1240         return err;
1241
1242 out_wait_error:
1243         sk->sk_state = SS_UNCONNECTED;
1244         sock->state = SS_UNCONNECTED;
1245         goto out_wait;
1246 }
1247
1248 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags)
1249 {
1250         struct sock *listener;
1251         int err;
1252         struct sock *connected;
1253         struct vsock_sock *vconnected;
1254         long timeout;
1255         DEFINE_WAIT(wait);
1256
1257         err = 0;
1258         listener = sock->sk;
1259
1260         lock_sock(listener);
1261
1262         if (sock->type != SOCK_STREAM) {
1263                 err = -EOPNOTSUPP;
1264                 goto out;
1265         }
1266
1267         if (listener->sk_state != SS_LISTEN) {
1268                 err = -EINVAL;
1269                 goto out;
1270         }
1271
1272         /* Wait for children sockets to appear; these are the new sockets
1273          * created upon connection establishment.
1274          */
1275         timeout = sock_sndtimeo(listener, flags & O_NONBLOCK);
1276         prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1277
1278         while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1279                listener->sk_err == 0) {
1280                 release_sock(listener);
1281                 timeout = schedule_timeout(timeout);
1282                 lock_sock(listener);
1283
1284                 if (signal_pending(current)) {
1285                         err = sock_intr_errno(timeout);
1286                         goto out_wait;
1287                 } else if (timeout == 0) {
1288                         err = -EAGAIN;
1289                         goto out_wait;
1290                 }
1291
1292                 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1293         }
1294
1295         if (listener->sk_err)
1296                 err = -listener->sk_err;
1297
1298         if (connected) {
1299                 listener->sk_ack_backlog--;
1300
1301                 lock_sock(connected);
1302                 vconnected = vsock_sk(connected);
1303
1304                 /* If the listener socket has received an error, then we should
1305                  * reject this socket and return.  Note that we simply mark the
1306                  * socket rejected, drop our reference, and let the cleanup
1307                  * function handle the cleanup; the fact that we found it in
1308                  * the listener's accept queue guarantees that the cleanup
1309                  * function hasn't run yet.
1310                  */
1311                 if (err) {
1312                         vconnected->rejected = true;
1313                         release_sock(connected);
1314                         sock_put(connected);
1315                         goto out_wait;
1316                 }
1317
1318                 newsock->state = SS_CONNECTED;
1319                 sock_graft(connected, newsock);
1320                 release_sock(connected);
1321                 sock_put(connected);
1322         }
1323
1324 out_wait:
1325         finish_wait(sk_sleep(listener), &wait);
1326 out:
1327         release_sock(listener);
1328         return err;
1329 }
1330
1331 static int vsock_listen(struct socket *sock, int backlog)
1332 {
1333         int err;
1334         struct sock *sk;
1335         struct vsock_sock *vsk;
1336
1337         sk = sock->sk;
1338
1339         lock_sock(sk);
1340
1341         if (sock->type != SOCK_STREAM) {
1342                 err = -EOPNOTSUPP;
1343                 goto out;
1344         }
1345
1346         if (sock->state != SS_UNCONNECTED) {
1347                 err = -EINVAL;
1348                 goto out;
1349         }
1350
1351         vsk = vsock_sk(sk);
1352
1353         if (!vsock_addr_bound(&vsk->local_addr)) {
1354                 err = -EINVAL;
1355                 goto out;
1356         }
1357
1358         sk->sk_max_ack_backlog = backlog;
1359         sk->sk_state = SS_LISTEN;
1360
1361         err = 0;
1362
1363 out:
1364         release_sock(sk);
1365         return err;
1366 }
1367
1368 static int vsock_stream_setsockopt(struct socket *sock,
1369                                    int level,
1370                                    int optname,
1371                                    char __user *optval,
1372                                    unsigned int optlen)
1373 {
1374         int err;
1375         struct sock *sk;
1376         struct vsock_sock *vsk;
1377         u64 val;
1378
1379         if (level != AF_VSOCK)
1380                 return -ENOPROTOOPT;
1381
1382 #define COPY_IN(_v)                                       \
1383         do {                                              \
1384                 if (optlen < sizeof(_v)) {                \
1385                         err = -EINVAL;                    \
1386                         goto exit;                        \
1387                 }                                         \
1388                 if (copy_from_user(&_v, optval, sizeof(_v)) != 0) {     \
1389                         err = -EFAULT;                                  \
1390                         goto exit;                                      \
1391                 }                                                       \
1392         } while (0)
1393
1394         err = 0;
1395         sk = sock->sk;
1396         vsk = vsock_sk(sk);
1397
1398         lock_sock(sk);
1399
1400         switch (optname) {
1401         case SO_VM_SOCKETS_BUFFER_SIZE:
1402                 COPY_IN(val);
1403                 transport->set_buffer_size(vsk, val);
1404                 break;
1405
1406         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1407                 COPY_IN(val);
1408                 transport->set_max_buffer_size(vsk, val);
1409                 break;
1410
1411         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1412                 COPY_IN(val);
1413                 transport->set_min_buffer_size(vsk, val);
1414                 break;
1415
1416         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1417                 struct timeval tv;
1418                 COPY_IN(tv);
1419                 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1420                     tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1421                         vsk->connect_timeout = tv.tv_sec * HZ +
1422                             DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1423                         if (vsk->connect_timeout == 0)
1424                                 vsk->connect_timeout =
1425                                     VSOCK_DEFAULT_CONNECT_TIMEOUT;
1426
1427                 } else {
1428                         err = -ERANGE;
1429                 }
1430                 break;
1431         }
1432
1433         default:
1434                 err = -ENOPROTOOPT;
1435                 break;
1436         }
1437
1438 #undef COPY_IN
1439
1440 exit:
1441         release_sock(sk);
1442         return err;
1443 }
1444
1445 static int vsock_stream_getsockopt(struct socket *sock,
1446                                    int level, int optname,
1447                                    char __user *optval,
1448                                    int __user *optlen)
1449 {
1450         int err;
1451         int len;
1452         struct sock *sk;
1453         struct vsock_sock *vsk;
1454         u64 val;
1455
1456         if (level != AF_VSOCK)
1457                 return -ENOPROTOOPT;
1458
1459         err = get_user(len, optlen);
1460         if (err != 0)
1461                 return err;
1462
1463 #define COPY_OUT(_v)                            \
1464         do {                                    \
1465                 if (len < sizeof(_v))           \
1466                         return -EINVAL;         \
1467                                                 \
1468                 len = sizeof(_v);               \
1469                 if (copy_to_user(optval, &_v, len) != 0)        \
1470                         return -EFAULT;                         \
1471                                                                 \
1472         } while (0)
1473
1474         err = 0;
1475         sk = sock->sk;
1476         vsk = vsock_sk(sk);
1477
1478         switch (optname) {
1479         case SO_VM_SOCKETS_BUFFER_SIZE:
1480                 val = transport->get_buffer_size(vsk);
1481                 COPY_OUT(val);
1482                 break;
1483
1484         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1485                 val = transport->get_max_buffer_size(vsk);
1486                 COPY_OUT(val);
1487                 break;
1488
1489         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1490                 val = transport->get_min_buffer_size(vsk);
1491                 COPY_OUT(val);
1492                 break;
1493
1494         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1495                 struct timeval tv;
1496                 tv.tv_sec = vsk->connect_timeout / HZ;
1497                 tv.tv_usec =
1498                     (vsk->connect_timeout -
1499                      tv.tv_sec * HZ) * (1000000 / HZ);
1500                 COPY_OUT(tv);
1501                 break;
1502         }
1503         default:
1504                 return -ENOPROTOOPT;
1505         }
1506
1507         err = put_user(len, optlen);
1508         if (err != 0)
1509                 return -EFAULT;
1510
1511 #undef COPY_OUT
1512
1513         return 0;
1514 }
1515
1516 static int vsock_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
1517                                 struct msghdr *msg, size_t len)
1518 {
1519         struct sock *sk;
1520         struct vsock_sock *vsk;
1521         ssize_t total_written;
1522         long timeout;
1523         int err;
1524         struct vsock_transport_send_notify_data send_data;
1525
1526         DEFINE_WAIT(wait);
1527
1528         sk = sock->sk;
1529         vsk = vsock_sk(sk);
1530         total_written = 0;
1531         err = 0;
1532
1533         if (msg->msg_flags & MSG_OOB)
1534                 return -EOPNOTSUPP;
1535
1536         lock_sock(sk);
1537
1538         /* Callers should not provide a destination with stream sockets. */
1539         if (msg->msg_namelen) {
1540                 err = sk->sk_state == SS_CONNECTED ? -EISCONN : -EOPNOTSUPP;
1541                 goto out;
1542         }
1543
1544         /* Send data only if both sides are not shutdown in the direction. */
1545         if (sk->sk_shutdown & SEND_SHUTDOWN ||
1546             vsk->peer_shutdown & RCV_SHUTDOWN) {
1547                 err = -EPIPE;
1548                 goto out;
1549         }
1550
1551         if (sk->sk_state != SS_CONNECTED ||
1552             !vsock_addr_bound(&vsk->local_addr)) {
1553                 err = -ENOTCONN;
1554                 goto out;
1555         }
1556
1557         if (!vsock_addr_bound(&vsk->remote_addr)) {
1558                 err = -EDESTADDRREQ;
1559                 goto out;
1560         }
1561
1562         /* Wait for room in the produce queue to enqueue our user's data. */
1563         timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1564
1565         err = transport->notify_send_init(vsk, &send_data);
1566         if (err < 0)
1567                 goto out;
1568
1569         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1570
1571         while (total_written < len) {
1572                 ssize_t written;
1573
1574                 while (vsock_stream_has_space(vsk) == 0 &&
1575                        sk->sk_err == 0 &&
1576                        !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1577                        !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1578
1579                         /* Don't wait for non-blocking sockets. */
1580                         if (timeout == 0) {
1581                                 err = -EAGAIN;
1582                                 goto out_wait;
1583                         }
1584
1585                         err = transport->notify_send_pre_block(vsk, &send_data);
1586                         if (err < 0)
1587                                 goto out_wait;
1588
1589                         release_sock(sk);
1590                         timeout = schedule_timeout(timeout);
1591                         lock_sock(sk);
1592                         if (signal_pending(current)) {
1593                                 err = sock_intr_errno(timeout);
1594                                 goto out_wait;
1595                         } else if (timeout == 0) {
1596                                 err = -EAGAIN;
1597                                 goto out_wait;
1598                         }
1599
1600                         prepare_to_wait(sk_sleep(sk), &wait,
1601                                         TASK_INTERRUPTIBLE);
1602                 }
1603
1604                 /* These checks occur both as part of and after the loop
1605                  * conditional since we need to check before and after
1606                  * sleeping.
1607                  */
1608                 if (sk->sk_err) {
1609                         err = -sk->sk_err;
1610                         goto out_wait;
1611                 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1612                            (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1613                         err = -EPIPE;
1614                         goto out_wait;
1615                 }
1616
1617                 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1618                 if (err < 0)
1619                         goto out_wait;
1620
1621                 /* Note that enqueue will only write as many bytes as are free
1622                  * in the produce queue, so we don't need to ensure len is
1623                  * smaller than the queue size.  It is the caller's
1624                  * responsibility to check how many bytes we were able to send.
1625                  */
1626
1627                 written = transport->stream_enqueue(
1628                                 vsk, msg->msg_iov,
1629                                 len - total_written);
1630                 if (written < 0) {
1631                         err = -ENOMEM;
1632                         goto out_wait;
1633                 }
1634
1635                 total_written += written;
1636
1637                 err = transport->notify_send_post_enqueue(
1638                                 vsk, written, &send_data);
1639                 if (err < 0)
1640                         goto out_wait;
1641
1642         }
1643
1644 out_wait:
1645         if (total_written > 0)
1646                 err = total_written;
1647         finish_wait(sk_sleep(sk), &wait);
1648 out:
1649         release_sock(sk);
1650         return err;
1651 }
1652
1653
1654 static int
1655 vsock_stream_recvmsg(struct kiocb *kiocb,
1656                      struct socket *sock,
1657                      struct msghdr *msg, size_t len, int flags)
1658 {
1659         struct sock *sk;
1660         struct vsock_sock *vsk;
1661         int err;
1662         size_t target;
1663         ssize_t copied;
1664         long timeout;
1665         struct vsock_transport_recv_notify_data recv_data;
1666
1667         DEFINE_WAIT(wait);
1668
1669         sk = sock->sk;
1670         vsk = vsock_sk(sk);
1671         err = 0;
1672
1673         msg->msg_namelen = 0;
1674
1675         lock_sock(sk);
1676
1677         if (sk->sk_state != SS_CONNECTED) {
1678                 /* Recvmsg is supposed to return 0 if a peer performs an
1679                  * orderly shutdown. Differentiate between that case and when a
1680                  * peer has not connected or a local shutdown occured with the
1681                  * SOCK_DONE flag.
1682                  */
1683                 if (sock_flag(sk, SOCK_DONE))
1684                         err = 0;
1685                 else
1686                         err = -ENOTCONN;
1687
1688                 goto out;
1689         }
1690
1691         if (flags & MSG_OOB) {
1692                 err = -EOPNOTSUPP;
1693                 goto out;
1694         }
1695
1696         /* We don't check peer_shutdown flag here since peer may actually shut
1697          * down, but there can be data in the queue that a local socket can
1698          * receive.
1699          */
1700         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1701                 err = 0;
1702                 goto out;
1703         }
1704
1705         /* It is valid on Linux to pass in a zero-length receive buffer.  This
1706          * is not an error.  We may as well bail out now.
1707          */
1708         if (!len) {
1709                 err = 0;
1710                 goto out;
1711         }
1712
1713         /* We must not copy less than target bytes into the user's buffer
1714          * before returning successfully, so we wait for the consume queue to
1715          * have that much data to consume before dequeueing.  Note that this
1716          * makes it impossible to handle cases where target is greater than the
1717          * queue size.
1718          */
1719         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1720         if (target >= transport->stream_rcvhiwat(vsk)) {
1721                 err = -ENOMEM;
1722                 goto out;
1723         }
1724         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1725         copied = 0;
1726
1727         err = transport->notify_recv_init(vsk, target, &recv_data);
1728         if (err < 0)
1729                 goto out;
1730
1731         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1732
1733         while (1) {
1734                 s64 ready = vsock_stream_has_data(vsk);
1735
1736                 if (ready < 0) {
1737                         /* Invalid queue pair content. XXX This should be
1738                          * changed to a connection reset in a later change.
1739                          */
1740
1741                         err = -ENOMEM;
1742                         goto out_wait;
1743                 } else if (ready > 0) {
1744                         ssize_t read;
1745
1746                         err = transport->notify_recv_pre_dequeue(
1747                                         vsk, target, &recv_data);
1748                         if (err < 0)
1749                                 break;
1750
1751                         read = transport->stream_dequeue(
1752                                         vsk, msg->msg_iov,
1753                                         len - copied, flags);
1754                         if (read < 0) {
1755                                 err = -ENOMEM;
1756                                 break;
1757                         }
1758
1759                         copied += read;
1760
1761                         err = transport->notify_recv_post_dequeue(
1762                                         vsk, target, read,
1763                                         !(flags & MSG_PEEK), &recv_data);
1764                         if (err < 0)
1765                                 goto out_wait;
1766
1767                         if (read >= target || flags & MSG_PEEK)
1768                                 break;
1769
1770                         target -= read;
1771                 } else {
1772                         if (sk->sk_err != 0 || (sk->sk_shutdown & RCV_SHUTDOWN)
1773                             || (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1774                                 break;
1775                         }
1776                         /* Don't wait for non-blocking sockets. */
1777                         if (timeout == 0) {
1778                                 err = -EAGAIN;
1779                                 break;
1780                         }
1781
1782                         err = transport->notify_recv_pre_block(
1783                                         vsk, target, &recv_data);
1784                         if (err < 0)
1785                                 break;
1786
1787                         release_sock(sk);
1788                         timeout = schedule_timeout(timeout);
1789                         lock_sock(sk);
1790
1791                         if (signal_pending(current)) {
1792                                 err = sock_intr_errno(timeout);
1793                                 break;
1794                         } else if (timeout == 0) {
1795                                 err = -EAGAIN;
1796                                 break;
1797                         }
1798
1799                         prepare_to_wait(sk_sleep(sk), &wait,
1800                                         TASK_INTERRUPTIBLE);
1801                 }
1802         }
1803
1804         if (sk->sk_err)
1805                 err = -sk->sk_err;
1806         else if (sk->sk_shutdown & RCV_SHUTDOWN)
1807                 err = 0;
1808
1809         if (copied > 0) {
1810                 /* We only do these additional bookkeeping/notification steps
1811                  * if we actually copied something out of the queue pair
1812                  * instead of just peeking ahead.
1813                  */
1814
1815                 if (!(flags & MSG_PEEK)) {
1816                         /* If the other side has shutdown for sending and there
1817                          * is nothing more to read, then modify the socket
1818                          * state.
1819                          */
1820                         if (vsk->peer_shutdown & SEND_SHUTDOWN) {
1821                                 if (vsock_stream_has_data(vsk) <= 0) {
1822                                         sk->sk_state = SS_UNCONNECTED;
1823                                         sock_set_flag(sk, SOCK_DONE);
1824                                         sk->sk_state_change(sk);
1825                                 }
1826                         }
1827                 }
1828                 err = copied;
1829         }
1830
1831 out_wait:
1832         finish_wait(sk_sleep(sk), &wait);
1833 out:
1834         release_sock(sk);
1835         return err;
1836 }
1837
1838 static const struct proto_ops vsock_stream_ops = {
1839         .family = PF_VSOCK,
1840         .owner = THIS_MODULE,
1841         .release = vsock_release,
1842         .bind = vsock_bind,
1843         .connect = vsock_stream_connect,
1844         .socketpair = sock_no_socketpair,
1845         .accept = vsock_accept,
1846         .getname = vsock_getname,
1847         .poll = vsock_poll,
1848         .ioctl = sock_no_ioctl,
1849         .listen = vsock_listen,
1850         .shutdown = vsock_shutdown,
1851         .setsockopt = vsock_stream_setsockopt,
1852         .getsockopt = vsock_stream_getsockopt,
1853         .sendmsg = vsock_stream_sendmsg,
1854         .recvmsg = vsock_stream_recvmsg,
1855         .mmap = sock_no_mmap,
1856         .sendpage = sock_no_sendpage,
1857 };
1858
1859 static int vsock_create(struct net *net, struct socket *sock,
1860                         int protocol, int kern)
1861 {
1862         if (!sock)
1863                 return -EINVAL;
1864
1865         if (protocol && protocol != PF_VSOCK)
1866                 return -EPROTONOSUPPORT;
1867
1868         switch (sock->type) {
1869         case SOCK_DGRAM:
1870                 sock->ops = &vsock_dgram_ops;
1871                 break;
1872         case SOCK_STREAM:
1873                 sock->ops = &vsock_stream_ops;
1874                 break;
1875         default:
1876                 return -ESOCKTNOSUPPORT;
1877         }
1878
1879         sock->state = SS_UNCONNECTED;
1880
1881         return __vsock_create(net, sock, NULL, GFP_KERNEL, 0) ? 0 : -ENOMEM;
1882 }
1883
1884 static const struct net_proto_family vsock_family_ops = {
1885         .family = AF_VSOCK,
1886         .create = vsock_create,
1887         .owner = THIS_MODULE,
1888 };
1889
1890 static long vsock_dev_do_ioctl(struct file *filp,
1891                                unsigned int cmd, void __user *ptr)
1892 {
1893         u32 __user *p = ptr;
1894         int retval = 0;
1895
1896         switch (cmd) {
1897         case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
1898                 if (put_user(transport->get_local_cid(), p) != 0)
1899                         retval = -EFAULT;
1900                 break;
1901
1902         default:
1903                 pr_err("Unknown ioctl %d\n", cmd);
1904                 retval = -EINVAL;
1905         }
1906
1907         return retval;
1908 }
1909
1910 static long vsock_dev_ioctl(struct file *filp,
1911                             unsigned int cmd, unsigned long arg)
1912 {
1913         return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
1914 }
1915
1916 #ifdef CONFIG_COMPAT
1917 static long vsock_dev_compat_ioctl(struct file *filp,
1918                                    unsigned int cmd, unsigned long arg)
1919 {
1920         return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
1921 }
1922 #endif
1923
1924 static const struct file_operations vsock_device_ops = {
1925         .owner          = THIS_MODULE,
1926         .unlocked_ioctl = vsock_dev_ioctl,
1927 #ifdef CONFIG_COMPAT
1928         .compat_ioctl   = vsock_dev_compat_ioctl,
1929 #endif
1930         .open           = nonseekable_open,
1931 };
1932
1933 static struct miscdevice vsock_device = {
1934         .name           = "vsock",
1935         .fops           = &vsock_device_ops,
1936 };
1937
1938 static int __vsock_core_init(void)
1939 {
1940         int err;
1941
1942         vsock_init_tables();
1943
1944         vsock_device.minor = MISC_DYNAMIC_MINOR;
1945         err = misc_register(&vsock_device);
1946         if (err) {
1947                 pr_err("Failed to register misc device\n");
1948                 return -ENOENT;
1949         }
1950
1951         err = proto_register(&vsock_proto, 1);  /* we want our slab */
1952         if (err) {
1953                 pr_err("Cannot register vsock protocol\n");
1954                 goto err_misc_deregister;
1955         }
1956
1957         err = sock_register(&vsock_family_ops);
1958         if (err) {
1959                 pr_err("could not register af_vsock (%d) address family: %d\n",
1960                        AF_VSOCK, err);
1961                 goto err_unregister_proto;
1962         }
1963
1964         return 0;
1965
1966 err_unregister_proto:
1967         proto_unregister(&vsock_proto);
1968 err_misc_deregister:
1969         misc_deregister(&vsock_device);
1970         return err;
1971 }
1972
1973 int vsock_core_init(const struct vsock_transport *t)
1974 {
1975         int retval = mutex_lock_interruptible(&vsock_register_mutex);
1976         if (retval)
1977                 return retval;
1978
1979         if (transport) {
1980                 retval = -EBUSY;
1981                 goto out;
1982         }
1983
1984         transport = t;
1985         retval = __vsock_core_init();
1986         if (retval)
1987                 transport = NULL;
1988
1989 out:
1990         mutex_unlock(&vsock_register_mutex);
1991         return retval;
1992 }
1993 EXPORT_SYMBOL_GPL(vsock_core_init);
1994
1995 void vsock_core_exit(void)
1996 {
1997         mutex_lock(&vsock_register_mutex);
1998
1999         misc_deregister(&vsock_device);
2000         sock_unregister(AF_VSOCK);
2001         proto_unregister(&vsock_proto);
2002
2003         /* We do not want the assignment below re-ordered. */
2004         mb();
2005         transport = NULL;
2006
2007         mutex_unlock(&vsock_register_mutex);
2008 }
2009 EXPORT_SYMBOL_GPL(vsock_core_exit);
2010
2011 MODULE_AUTHOR("VMware, Inc.");
2012 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2013 MODULE_VERSION("1.0.0.0-k");
2014 MODULE_LICENSE("GPL v2");